Apparatus and method of processing raw materials

ABSTRACT

A method and apparatus for processing animal byproduct materials is disclosed. In some embodiments, the apparatus includes a grinder for grinding the byproduct materials; a mixer for mixing the ground byproduct materials with an oil absorbing material and a backmix material; and a dryer for drying the mixed materials. In some embodiments, the apparatus also includes a cyclone for separating an air stream from the dried materials. The dried materials are transported to one or more presses for pressing the dried materials, thereby reducing oil content. The one or more presses includes a first opening for delivering pressed oil to a centrifuge and a second opening for sending the pressed materials to a screener. A portion of the screened material is sent back to the mixer (and/or the grinder) and the balance of the screened material are sent to storage as a finished product.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is based on and claims priority to U.S.Provisional Patent Application No. 60/715,408, filed Sep. 9, 2005,entitled “Apparatus and method of processing raw materials,” by the sameinventors. This application incorporates U.S. Provisional PatentApplication No. 60/715,408, filed Sep. 9, 2005, and entitled “Apparatusand method of processing raw materials” in its entirety by reference.

FIELD OF THE INVENTION

This invention relates to rendering processes. More specifically, thisinvention relates to an improved method and apparatus for processinganimal byproduct materials having an original moisture content of about50 to 80 percent, that grinds and mixes the materials with an oilabsorbing material and a backmix material and then dries the mixedmaterials, resulting in a final product containing about 2 to about 25percent moisture.

BACKGROUND OF THE INVENTION

Rendering is an industrial process that converts raw materials intostable, value-added materials. The process involves heating or cookingof raw materials to liquefy and separate fat from animal tissues. Themajority of tissue processed comes from slaughterhouses but alsoincludes restaurant grease and butcher shop trimmings. This material caninclude the fatty tissue, bones, and offal, as well as entire carcassesof animals condemned at slaughterhouses, and those that have died onfarms or in transit. The most common animal sources are beef, pork,sheep, poultry and fish.

Generally, the rendering process is accomplished by receiving rawmaterials, such as animal byproduct materials, followed by removingundesirable parts, cutting, mixing, cooking and separating fat andprotein materials. The concentrated protein is then dried and ground.The rendering process yields a fat commodity and a protein meal.Additionally, refining of gases, odors, and wastewater is necessary.After rendering, the materials are much more resistant to spoiling. Thefat can be used in animal feed, as a raw material for biodieselproduction, and as a feed-stock for the chemical industry. The bone andprotein becomes dry particles known as meat and bone meal, and can befed to certain animals.

FIG. 1 discloses a conventional apparatus 100 utilized in an animalbyproduct rendering process. Raw material to be rendered is received fortemporary storage in raw material bins 120. The raw material is thenconveyed to a raw material grinder 125 that reduces the raw material toa uniform particle size for material handling and improved heat transferfor cooking. The ground raw material is fed into a cooker 130. Thecooker 130 is heated by a boiler 135 generating boiler steam. The boilerbrings the raw material to a predetermined and elevated temperature,evaporating moisture and freeing fat from protein and bone. A dehydratedslurry of fat and solids is discharged from the cooker 130 at acontrolled rate. The discharged slurry is transported to an oil drainer160. The drainer 160 separates liquid fat from the solids. The liquidfat is pumped to an oil centrifuge 165, which removes impurities fromthe fat. The fat is transported to the storage 168 as finished fat. Thesolids from the drainer 160 go to the presses 170, which reduce thesolids' fat content further. Solids discharged from the presses go to agrinding room 175, a hammermill 180, and a screener 185 for furtherscreening and processing of the solids, where they are transported tothe storage 190 as a finished product.

Still referring to FIG. 1, water vapor exits the cooker 130 to acondenser 150, which condenses the water vapor. The condensed vapors areeventually discharged as waste water. Odorous gases generated at variouspoints in the rendering process are collected for neutralization andremoval by a scrubber 140.

The conventional rendering process of FIG. 1 has several disadvantages.Cookers generate strong odors and the cookers use in the renderingprocess requires expensive odor control equipment, such as scrubbers,condensers and waste water storage. These odor-control and odor-causingsources require increased personnel labor, water use, energyconsumption, and adequate cooling capacity, in addition to their costs.

U.S. Pat. No. 5,759,568 describes a method of processing a waste waterstream into animal foodstuffs. The '568 patent is based on addition ofbentonite and a polymer to a food processing plant's waste water stream.The '568 patent describes the process as a combination of, at least,three aqueous streams, so that the final stream can be substantiallydiluted. This is confirmed by the use of a flotation vessel forsolids-water separation, resulting in the discharge of the effluent intothe sewer system. A drawback of the invention is that the flotationprocess results in separated solids containing abundant moisture, andthe effluent containing residual suspended solids. The bentonitematerial has to be hydrated prior to mixing with the waste water stream.The '568 patent is thus limited to diluted waste water streams. The '568patent also uses filter presses for sludge dewatering that significantlyadds to the cost of the process.

SUMMARY OF THE INVENTION

An apparatus and method of processing animal byproduct materials isdisclosed. In one embodiment, the apparatus comprises a grinder forgrinding the byproduct materials; a mixer for mixing the groundbyproduct materials with an oil absorbing material and a backmixmaterial; and a dryer for drying the mixed materials. In someembodiments, the apparatus includes a cyclone for separating an airstream from the dried materials. Alternatively, a bag house is used forseparating an air stream from the dried materials. In some embodiments,the air stream is drawn into a scrubber while the dried materials aretransported to one or more presses. The presses press the driedmaterials, reducing oil content from the dried materials. In someembodiments, the presses include a first opening for delivering pressedoil to a centrifuge and a second opening for transporting the pressedmaterials to a screener through a hammermill. From the screener, aportion of the screened material is sent back to the mixer and/or thegrinder. The balance of the screened material is sent to storage asfinished product. In some embodiments, the backmix materials are driedbackmix materials.

The byproduct materials can have an original moisture content of about50 to about 80 percent. In one embodiment, the byproduct materials havean original moisture content of about 70 percent. The ground and mixedmaterials contain less than 70 percent and greater than about 30 percentmoisture prior to drying. In one embodiment, the ground and mixedmaterials contain about 50 percent moisture prior to drying. The driedmaterials contain about 2 to about 25 percent moisture. In oneembodiment, the dried materials contain about 10 percent moisture.

In another embodiment of the present invention, a method of processinganimal byproduct materials is disclosed. The method comprises grindingthe byproduct materials; mixing the ground byproduct materials with anoil absorbing material and a backmix material; and drying the mixedmaterials. In some embodiments, the method also includes separating anair stream from the dried materials. In some embodiments, the methodfurther includes transporting the dried materials to one or more pressesfor pressing the dried materials, thereby reducing oil content from thedried materials, and drawing the air stream to a scrubber. In someembodiments, the method further includes delivering pressed oil to acentrifuge through a first opening of the presses and transporting thepressed materials to a screener via a hammermill through a secondopening of the one or more presses. In some embodiments, the methodfurther includes sending a portion of the screened materials back to themixer (and/or the grinder) and storing the balance of the screenedmaterial as a finished product. In some embodiments, the backmixmaterial is a dried backmix material.

The byproduct materials can have an original moisture content of about50 to about 80 percent. In one embodiment, the byproduct materials havean original moisture content of about 70 percent. The ground and mixedmaterials resulting from mixing the ground byproduct materials containsless than 70 percent and greater than about 30 percent moisture prior todrying the mixed materials. In one embodiment, the ground and mixedmaterials contain about 50 percent moisture prior to drying. The driedmaterials resulting from drying the mixed materials contain about 2 toabout 25 percent moisture.

In another embodiment of the present invention, an apparatus forprocessing animal byproduct materials is disclosed. The apparatuscomprises a grinder for grinding the byproduct materials; a mixer formixing the ground byproduct materials with an oil absorbing material anda backmix material; a dryer for drying the mixed materials; and acyclone (or bag house) for separating an air stream from the driedmaterials.

In another embodiment of the present invention, a method of processinganimal byproduct materials is disclosed. The method comprises grindingthe byproduct materials; mixing the ground byproduct materials with anoil absorbing material and a backmix material; drying the mixedmaterials; and separating an air stream from the mixed materials.

In another embodiment of the present invention, an apparatus forprocessing animal byproduct materials containing about 50 to about 80percent moisture is disclosed. The apparatus comprises a grinder forgrinding the byproduct materials and a mixer for mixing the groundbyproduct materials with an oil absorbing material and a dried backmixmaterial. The ground and mixed materials contains less than 70 percentand greater than about 30 percent moisture. The apparatus also comprisesa dryer for drying the mixed materials. The dried materials containabout 2 to about 25 percent moisture.

In another embodiment of the present invention, a method of processinganimal byproduct materials containing about 50 to about 80 percentmoisture is disclosed. The method comprises grinding the byproductmaterials and mixing the ground byproduct materials with an oilabsorbing material and a dried backmix material, resulting in a moisturecontent of less than 70 percent and greater than about 30 percent. Themethod also comprises drying the mixed materials, resulting in amoisture content of about 2 to about 25 percent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a conventional apparatus utilized in animal byproductrendering processes.

FIG. 2 shows an apparatus utilized in an animal byproduct renderingprocess, according to one embodiment of the present invention.

FIG. 3 shows a flow chart of an animal byproduct rendering process,according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The present invention is directed to an improved method and apparatusfor processing animal byproduct materials. FIG. 2 shows an apparatus 200according to one embodiment of the present invention. The apparatus 200includes a raw material grinder 230 for grinding raw material 210. Theraw material 210 is preferably an animal byproduct material having anoriginal moisture content of about 50 to about 80 percent, a fat contentof approximately 10 to about 50 percent, and a protein content of about10 to about 50 percent. In one embodiment, the original moisture contentof the raw material is approximately 70 percent. In some embodiments, anoil absorbing material, such as a bentonite clay material, from a clayfeeder 220 is mixed with the raw material 210 in the grinder or in amixer 240. The oil absorbing material is preferably a carrier to helpcarry the oil. The mixer 240 mixes the ground raw material with the oilabsorbing material and a backmix material. In some embodiments, thebackmix material is any dried animal byproduct material, such as offal.The ground and mixed materials contain less than 60 percent and greaterthan about 40 percent moisture prior to drying. In one embodiment, theground and mixed materials contain approximately 50 percent moistureprior to drying. The mixed materials are then conveyed to a dryer 250for drying the mixed materials. The dried materials contain about 2 toabout 25 percent moisture. In one embodiment, the dried materialscontain approximately 10 percent moisture. The dried materials are thensent to a cyclone 260 for separating an air stream from the driedmaterials. In one embodiment, the cyclone 260 is replaced by a bag house(not shown) for separating an air stream from the dried materials. Theair stream is drawn into an optional scrubber 320 by a fan 310. In someembodiments, the optional scrubber 320 is coupled to the apparatus 200to further remove any odoriferous materials and any off-gasses. Thedried materials are transported to one or more presses 270 through anairlock 265. The one or more presses 270 press the dried materials,reducing oil content from the dried materials. The one or more presses270 include a first opening for delivering pressed oil to a centrifuge275 and a second opening for transporting the pressed materials to ascreener 290 through a hammermill 280. From the screener 290, a portionof the screened material is sent back to the mixer 240. Alternatively,in some embodiments, a portion of the screened material is sent to thegrinder 230. The balance of the screened material is sent to storage 300as finished product or meal.

The dried materials exiting the cyclone 260 (or bag house)—prior tobeing fed to the presses 270—contain approximately 10 to 40 percent fatand approximately 2 to about 25 percent moisture. The dried materialscontaining these fat and moisture contents are pressed by the presses270, resulting in a dried material having approximately 10 percent fatand approximately 10 percent moisture or less. The pressed fat (oil),which is sent to the centrifuge 275, can be used as fuel or as fish oil.

The dryer 250 of the present invention preferably contains a first zoneand a second zone. In the first zone, air enters the dryer 250,preferably between 300 to 1,000 degrees Fahrenheit, through an air inletwhere it encounters the mixed materials also being fed to the dryer 250.The majority of moisture evaporation occurs in the first zone. As themixed materials proceed through the second zone, secondary drying takesplace to achieve moisture content as low as less than 10 percent.

FIG. 3 shows a flow chart of an animal byproduct rendering process 400,according to another embodiment of the present invention. In the Step410, the byproduct materials are ground. In the Step 420, the groundmaterials are mixed with an oil absorbing material and a backmixmaterial. In the Step 430, the mixed materials are dried. In someembodiments, the process 400 also includes the step of separating an airstream from the dried materials. In some embodiments, the process 400further includes the steps of transporting the dried materials to one ormore presses, thereby reducing oil content from the dried materials, anddrawing the air stream to a scrubber. In some embodiments, the process400 further includes the steps of delivering pressed oil to thecentrifuge through a first opening of the screener and transporting thepressed materials to a screener through a second opening of the presses.In some embodiments, the process 400 further includes the steps offeeding the pressed material to the screener from the presses through ahammermill and sending a portion of the screened material back to themixer and/or the grinder.

The present invention offers any processor the ability to generaterevenue via processing their raw material. The present invention offersany processor the ability to dry a raw material that is high in proteinand fat content. The present invention grinds and dries an originalanimal byproduct material containing about 50 to about 80 percentmoisture to a finished protein meal containing about 2 to about 25percent moisture. With this invention, a processor is able to eliminatenumerous steps that are typically required to separate the fat from theprotein meal. For example, the present invention eliminates the need forwaste water treatment, along with condensers, oil (fat) drainers, andcookers, as required in many conventional rendering plants. The presentinvention requires less capitol cost and man power, and can beintegrated into any existing plant, resulting in a finished product ofhigher quality and an overall process having less environmentalconcerns, such as odor. The present invention allows any processor tocompetitively operate a continuous rendering process system on site. Thepresent invention can process 300,000 pounds per week for the sameaverage per pound production cost as another facility that processes6,000,000 pounds per week. Processing on site eliminates freightexpenses of shipping the raw material to an off-site renderingoperation.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding ofprinciples of construction and operation of the invention. Suchreference herein to specific embodiments and details thereof is notintended to limit the scope of the claims appended hereto. It will beapparent to those skilled in the art that modification may be made inthe embodiments chosen for illustration without departing from thespirit and scope of the invention.

1. An apparatus for processing animal byproduct materials, comprising: a. a grinder for grinding the byproduct materials; b. a mixer for mixing the ground byproduct materials with an oil absorbing material and a backmix material, wherein the backmix material is a portion of a finished product; and c. a dryer for drying the mixed materials.
 2. The apparatus of claim 1 further including a cyclone for separating an air stream from the dried materials.
 3. The apparatus of claim 1 further including a bag house for separating an air stream from the dried materials.
 4. The apparatus of claim 2 wherein the air stream is drawn into a scrubber and the dried materials are transported to one or more presses for pressing the dried materials, thereby reducing oil content from the dried materials.
 5. The apparatus of claim 4 wherein the one or more presses includes a first opening for delivering pressed oil to a centrifuge and a second opening for transporting the pressed materials to a screener.
 6. The apparatus of claim 5 wherein a portion of the screened material is sent back to the mixer and the balance of the screened material are sent to storage as a finished product.
 7. The apparatus of claim 5 wherein a portion of the screened material is sent back to the grinder and the balance of the screened material are sent to storage as a finished product.
 8. The apparatus of claim 1 wherein the byproduct materials have an original moisture content of about 50 to about 80 percent.
 9. The apparatus of claim 8 wherein the ground and mixed materials contain less than 70 percent and greater than about 30 percent moisture prior to drying.
 10. The apparatus of claim 9 wherein the dried materials contain about 2 to about 25 percent moisture.
 11. The apparatus of claim 1 wherein the backmix material is a dried backmix material. 12-43. (canceled) 